Ply board or sheet



Feb. 6, 1923. Y lAASZ l s. E. sAuNDE-:Rs

FLY BOARD 0R SHEET Filed Aug. 1].I 1919 ela.. 65, i923..

@eineao rnv Ronan or. snaar.

Application led August 11, 1919. Serial No. 316,817.

To all whom t may concern.'

Be it known that l, SAMUEL EDGAR SAUN- Dnns, a subject of the King ofGreat Britain, residing at Badmore House, lWhippingham, Isle oflll/light, England, have invented a new and useful Ply Board or Sheet(for which l have filed an application in England April 15, 1916, PatentNo. 105,412), of which the following is a specication.

My invention relates to the manufacture of ply boards or sheetscomprising a series or plurality of thin veneers secured together andchiefly intended for the construction of the hulls of boats,launches'and the like or of aircraft, but also applicable for a varietyof'other purposes.

ln the specification of former British Letters Patent granted to me No.222 A. D. 1898, l describe' a construction wherein a series of thinsheets or veneers of wood, after having been laid upon one another andmoulded to the form of a boat, launch or other structure, are securedtogether by wire lacing. Also in the specification of my former BritishPatent No. 19,516 A. D. 1914, l describe the use of thread or wirestitching.

This method of connecting a series of sheets or layers gives mostsatisfactory results in practice, but the connecting of the severallayers in situ is a somewhat slow process and is, consequently,relatively eX- pensive.

The object of my invention is to provide means whereby the constructionof aircraft, boats and other structures in which sewn `wood sheeting` isemployed is accelerated,

and to this end it comprises the improvements hereinafter described.

According to my invention l construct ply boards or sheets comprisingseveral layers of thin board or veneer connected by thread, twine orlike stitching vand sufficiently pliable to enable them to be moulded orbent to the desired form.

My invention will be readily understood by reference to the accompanyingdrawing, in which l y Figure l is an elevation of a piece of ply boardmade in accordance with my invention, and

Figures 2 and 3 are respectively longitudinal and transverse sectionsthereof.

a, an, a indicate number of layers of thin board or material which arearranged in a well known manner so that the grain of each layer crossesthe. grain of the adjacent layer or layers and which layers are usuallyconnected with one another by cement, with or -without interveninglayers of canvas or other fabric or material.

The several layers having been arranged the whole is stitched togetherby means of thread, twine or the like, as indicated at In practice thisstitching may be applied by means of a sewing machine which, of course,must possess sufficient strength to allow of the needle penetrating theseveral layers of material.

As shown in Figure 2 the stitching is represented as being of the kindapplied by means of a 1ockstitch machine.

ln order to provide a smooth surface, the sheets after having been sewncan be passed through rollers or pressed or otherwise treated, for thepurpose of compressing the stitching so that it does not project. In

practice, however, I prefer to form grooves c in the outer face of thesheet, as shown in Figures l. 2 and 3. in which grooves the stitcheswill lie and which can be filled with cement so as to effectually sealthe threads. N hen the grooves are formed, the sheet which is groovedmust be sufficiently stout to prevent it from being unduly weakened bythe lgrooving.

In the drawing the stitches are represented as being in straight linesbut it is to be understood that they may be in curved or sinuous linesas indicated by the dotted lines c?, in Figure 1, or they may be inzig-zag lines, or placed in any other convenient manner. Either or bothsurfaces of the sheet may have a layer of waterproof or other fabricapplied, either before or after the stitching operation.

Ply boards or .Sheets made in the manner described are very pliable andeen be readily bent., Within certain limits7 to Conform to theeoniguifation of the 'Framing to which Jhey are to be applied.Furtheiiiioe, `the 5 sheets can be made of considerable Width and ofpractically my required length,

thereby allowing large areas of 'framing to be Covered in e i'eletivelyShort time.

Having 110W patieularly descibecl and 'l0 ascertained the nature of theseid invention and in4 Whatinemier the same is lso be peirk omed, Ideclare `that what claim isz- A ply board orlsheeirI Comprising a numbefoi layers of thin board connected together by pairs of threads, one ofthe membeire o' each pair lying in groom/e in the surface of the sheetand the said members beingI intelloclefl together at inteivele iii'thebody of the sheet.

SAMUEL EDGAR SAUNDERS.

